PURPOSES : Advancements in science and technology caused by industrialization have led to an increase in particulate matter emissions and, consequently, severity of air pollution. Nitrogen oxide (NOx), which accounts for 58% of road transport pollutants, adversely affects both human health and the environment. A test-bed was constructed to determine NOx removal efficiency at the roadside. TiO2, a material used to reduce particulate matter, was used to remove NOx. It was applied to a vertical concrete structure using the dynamic pressurized penetration TiO2 fixation method, which can be easily applied to vertical concrete structures. This study was conducted to evaluate the NOx removal efficiency of the dynamic pressurized-penetration TiO2 fixation method in a test-bed under real roadside conditions. METHODS : A test-bed was constructed in order to determine the NOx removal efficiency using the dynamic pressurized penetration TiO2 fixation method on the roadside. The dynamic pressurized-penetration TiO2 fixation method was applied by installing a vertical concrete structure. NOx was injected into the test-bed using an exhaust gas generator. By installing a shading screen, the photocatalytic reaction of TiO2 was suppressed to a maximum concentration of 1000 ppb along the roadside. The removal efficiency was evaluated by measuring NOx concentrations. In addition, illuminance was measured using an illuminance meter. RESULTS : From the results of the analysis of the NOx removal efficiency in the test-bed which the dynamic pressurized type TiO2 fixation method was applied to, an average removal efficiency ranging from 18% to 40% was achieved, depending on the illuminance. Similarly, according to the results of the evaluation of the NO removal efficiency, an average of removal efficiency ranging from 20% to 62% was achieved. Thus, the NOx removal efficiency increased when the illuminance was high. CONCLUSIONS : From the results of the experiment conducted, the efficiency of NOx removal per unit volume was obtained according to the illuminance of TiO2 concrete along an actual road. Field applicability of the dynamic pressurized-penetration-type TiO2 fixation method to vertical concrete structures along roads was confirmed.

The objectives of this study were to analyze the fish community structures and distribution characteristics of fisheries resources in the Osip Stream and Wangpi Stream, fishery resources protection areas. For the study, we conducted fish samplings four times in the two streams from April to October 2019. In Osip Stream and Wangpi Stream, we sampled 31 species and 29 species and the dominant species were Zacco platypus (28.6%) and Squalidus multimaculatus (41.7%), respectively. According to the life type of fish species, primary freshwater species were collected 18 species (58.1%) and 21 species (72.4%), and migration fishes were sampled 4 species (12.9%) and 6 species (20.7%) in Osip Stream and Wangpi Stream, respectively. Fisheries resources species showed high relative abundance in June, and the fish biomass was highest in October. As a results of comparing the previous studies with this study, both rivers showed high biodiversity and were found to maintain stable populations of fishes. According to analysis of tolerance guilds, the proportion of tolerant species, based on the number of individuals, was composed of 14.4% and 1.1% in Osip Stream and Wangpi Stream, respectively. This very low ratio of tolerant species confirmed that both streams have very good physiochemical environment conditions. From the above results, it was judged that the fishery resource protection areas of Osip Stream and Wangpi Stream have high ecological function and preservation value. For sustainable use and management of fishery resource protection areas of Osip Stream and Wangpi Stream, it is suggested that biological disturbance management, fish discharge projects considering environmental capacity, efforts to improve the habitat environment, and establishing a fishery resource protection areas management system were necessary as considerations.

A timber lattice roof, which has around 30m span, was constructed. In order to figure out the realistic buckling load level, the structural analysis of this roof structure was performed especially by stiffness of connection with various asymmetric snow load. Due to the characteristics of application of snow load, the load combinations of snow should be considered not only global area but also local part so that the critical buckling load could be observed as easy as possible. Geometrical imperfection was simulated to consider inaccurate shape of structure. And then nonlinear analysis were performed. Finally, this paper could investigate that the asymmetric snow load with the lower level stiffness of connection decreased the level of buckling load significantly.

The structural analysis module is an essential part of any integrated structural system. Diverse integrated systems today require, from the analysis module, efficient real-time responses to real-time input such as earthquake signals, extreme weather-related forces, and man-made accidents. An integrated system may also be for the entire life span of a civil structure conceived during the initial conception, developed throughout various design stages, effectively used in construction, and utilized during usage and maintenance. All these integrated systems’ essential part is the structural analysis module, which must be automated and computationally efficient so that responses may be almost immediate. The finite element method is often used for structural analysis, and for automation, many effective finite element meshes must be automatically generated for a given analysis. A computationally efficient finite element mesh generation scheme based on the r-h method of mesh refinement using strain deviations from the values at the Gauss points as error estimates from the previous mesh is described. Shape factors are used to sort out overly distorted elements. A standard cantilever beam analyzed by four-node plane stress elements is used as an example to show the effectiveness of the automated algorithm for a time-domain dynamic analysis. Although recent developments in computer hardware and software have made many new applications in integrated structural systems possible, structural analysis still needs to be executed efficiently in real-time. The algorithm applies to diverse integrated systems, including nonlinear analyses and general dynamic problems in earthquake engineering.

본 연구는 1974년부터 2003년까지 김홍도의 주일 낮 예배 설교 중 기도를 주제로 삼는 40여 편을 선별하여, 설교 구성과 내용 그리고 삼중구조의 의의를 밝혀 구령 활동과의 연관성을 통하여 선교적 의미를 발견하게 된다. 설교 구성은 신구약 성경 구절을 균형 있게 자주 인용하 였으며, 성경과 교회의 역사에 있었던 기도 인물들 이야기와 기도에 관한 격언들을 적절히 활용함을 보여준다. 설교 주제는 기도의 동기와 원리를 먼저 선포하고, 기도 방법과 결과를 다루고 있다. 이처럼 기도의 동기, 방법, 결과에 대하여 삼중구조로 기도의 실천을 종합한다. 첫째, 개인의 영역에 제한되지 않고, 그 대상이 전방위적으로 통전적 모습을 보여주고 있다. 둘째, 교회 역사 속 기도의 인물들과 격언을 인용하여 교인들에게 기도의 실천적인 부분을 강조하게 된다. 셋째, 쉽고 반복되 는 설교 내용은 교인들에게 삶 속에서도 나눌 수 있도록 선교적 기도 영성을 적극적으로 활용하였다. 이러한 삼중구조와 각 내용의 균형은 영혼 구원이라는 목적을 이루기 위하여 통전적, 실천적, 선교적이다.

본 논문은 코시 모멘텀(Cauchy’s Momentum) 방정식을 이산화하기 위해 GC-LSM(Geometric Conservative Least Squares Method) 을 사용한 새로운 Meshless 방법을 제시한다. FEM(Finite Element Method) 방법이 구조해석에 널리 사용되고 있지만 무격자 기법은 격자를 이동해야 할 때 장점이 많기 때문에 개발되었다. 본 작업은 무격자 기반의 FSI(Fluid-Structure Interaction) 프로그램을 개발하 기 위한 기틀을 다지는 단계이다. 본 논문에서는 Cauchy’s Momentum 방정식을 GC-LSM을 사용하여 강형식 형태로 이산화하였고, 시간 적분을 위해 New Mark Beta 방법을 사용하였다. 개발된 기법은 1D, 2D 및 3D 벤치마킹 문제에서 검증했으며, 정적 해석 및 동적 해석 결과가 해석해와 비교시 매우 정확한 결과를 보여준다.

본 연구에서는 동명대학교 조선해양시뮬레이션센터의 Real-time 조종 및 작업 시뮬레이터를 활용한 해양구조물 설치 작업 시뮬 레이션을 통해 대상의 동적 특성 및 물리적 현상을 작업, 조종 사이의 상호 영향과 함께 분석한다. 8개의 계류삭에 의해 계류되는 반잠수 식 시추선의 설치 작업 시뮬레이션이 실제 현장에서의 작업과 유사한 시나리오로 수행되었고, 시추선의 위치 제어를 위한 예인선 4척와 계류삭의 Hook-up 작업을 위한 해양플랜트 지원 선박 1척이 운용되었다. 설치 작업이 수행되는 동안 대상들의 운동과 이동 경로, 계류삭 및 예인줄에 가해지는 장력 등을 실시간으로 확인하였으며, 이를 작업 과정별로 구분하여 분석하였다. 작업과 조종 시뮬레이션이 동시에 수행된 본 연구로부터 특정 환경 외력하에서 설치되는 해양구조물과 이를 위해 운용되는 선박들의 작업 절차에 따른 세부적인 거동 및 작업·조종 간의 상호 영향을 확인하였고, 이는 해상 상태 등을 고려한 해양구조물 설치 작업의 수행 가능 여부를 판단하기 위한 근거로 활용될 수 있음을 제시하였다.

Korean architecture classifies Banja (the decorated flat of the ceiling visible from the inside) of Royal Palaces into two types: Woomul(water-well, 井) banja, which inserts rectangular wooden board into lattice frame, and paper banja, which applies paper to the flat ceiling. Such classification was established in the 19th century. Before that, Banja was classified according to what was inserted into the lattice frame, either wooden or paper board. At first, the banja that used paper board was widely installed regardless of the purpose or nobility of the building. However, since the 17th century, the use of paper board banja became mostly restricted to Ondol (Korean floor heating system) rooms which are characterized by private usage and the importance of heating, and it was considered inferior to wooden board banja in terms of rank or grace. The contemporary paper banja was mainly installed in low-rank ondol rooms until the late 19th century to early 20th century, when roll-type wallpaper was introduced from the West and the paper banja came to decorate the King’s and Queen’s bedrooms. The traditional paper board banja benefits heat reservation, reduces the weight of the ceiling, and allows the adjustment of the lattice frame size. Furthermore, it can feature unique artistry if covered with blue, white, or red Neung-hwa-ji (traditional flower pattered paper).